Liquid Covering Disks and Systems

ABSTRACT

Liquid covering disks configured to float on the surface of a body of liquid, including a body with an aperture at a periphery of the body, the aperture configured to allow a liquid to pass through, a plurality of ribs projecting from the body, and a wall protruding at the periphery of the body. A portion of the body, a portion of the plurality of ribs, and a portion of the wall define a cavity allowing a volume of a gas to be trapped in the cavity when the disk is deployed on the surface of the body of liquid. In some examples, a system of floating disks covers the surface of a body of liquid. Each disk includes an interlocking element configured to interact with a complementary interlocking element at an adjacent disk to form a floating arrangement of disks.

BACKGROUND

The present disclosure relates generally to liquid covering disks and systems. In particular, this disclosure describes floating disks including a shape and a structure that provide stability to the disks and adherence to the surface when the disks are deployed on a surface of a body of liquid.

Ponds, reservoirs, and open tanks are often used to store and treat liquids. Liquids having large open surfaces are common in the fields of chemical production, anodizing, galvanizing, plating, dying, sewage treatment, oil waste storage, and other such fields. In many of these fields, unimpeded access to the liquid is desired. However, having large open liquid surfaces may lead to evaporation of the stored liquid, unintended plant and organism growth on the liquid surface, emission of noxious fumes, and exposure to wildlife.

Reducing fluid loss, toxic vapors emission, and heat loss are major environmental and financial concerns. Reducing evaporation and heat transfer is influenced by a variety of factors, such as wind conditions above the liquid surface, liquid temperature, environment temperature, liquid density, and the concentration of the substance evaporating in the air. Reducing evaporation will also reduce noxious fumes.

Some liquid covers presently understood in the art are polygonal shaped covers designed to be placed on the surface in concert, covering the liquid body. Examples of references describing such covers include U.S. Pat. Nos. 4,270,232 and 8,342,352 and European Patent No. 1,697,234. The complete disclosures of these patents and patent applications are herein incorporated by reference for all purposes.

In high velocity wind conditions, however, known liquid covers tend to be blown off the surface of the ponds, leaving significant surface on the liquid body exposed. Heavier designs that are less affected by the wind suffer from high shipping costs.

As a result, known liquid covering disks are not entirely satisfactory for the range of applications in which they are employed. Specifically, there exists a need for liquid coverings that protect against the harms listed above, while being wind resistant, easily adaptable to various liquid bodies, and of limited cost to manufacture. Examples of new and useful liquid covering disks relevant to the needs existing in the field are discussed below.

SUMMARY

The present disclosure is directed to liquid covering disks and systems. In some examples, a disk configured to float on the surface of a body of liquid includes a body, a plurality of ribs projecting from the body, and a sidewall protruding at the periphery of the body. The body has a top surface, a bottom surface, and an aperture at a periphery of the body. The aperture is configured to allow a liquid to pass through. A portion of the body, a portion of the plurality of ribs, and a portion of the sidewall define a cavity allowing a volume of a gas to be trapped in the cavity when the disk is deployed on the surface of the body of liquid and providing buoyancy to the disk.

In some embodiments, the body may include a polygonal shape. In other embodiments, the plurality of ribs radiate outward from the center of the polygonal shape towards the edges of the polygonal shape. In some embodiments, the plurality of ribs extend from the top surface and from the bottom surface of the body. In further embodiments, the ribs have a height above the body that decreases from a center of the body towards the periphery of the body.

In some embodiments, the body includes a cross-sectional profile that decreases from a center of the body to the periphery of the body. In other embodiments, the sidewall protrudes from the top surface and from the bottom surface. The sidewall may include a concave portion and/or a convex portion. In further embodiments, the aperture is positioned adjacent the sidewall. In some embodiments, the sidewall includes a sigmoidal curvature along the periphery of the body. In other embodiments, the aperture follows a contour of the curvature.

The inventive subject matter further contemplates a system for covering a surface of a body of liquid, including a plurality of disks configured to float on the surface of the body of liquid. The plurality of disks unite when floating on the surface of the body of liquid to form an arrangement of floating disks. Each of the plurality of disks includes an interlocking element configured to interact with a complementary interlocking element at an adjacent disk to assist in keeping the arrangement of floating disks together.

The interlocking elements may include a portion of the sidewall, a curvature of the sidewall, and/or a sigmoidal curvature of the sidewall extending from the bottom surface of the body and an inverse curvature extending from the top surface at a corresponding location of the body.

In further embodiments, a system for covering a surface of a body of liquid includes a plurality of disks configured to float on the surface of the body of liquid, each disk including a body having a substantial polygonal shape in the horizontal floating plane, the body including a top surface and a bottom surface, a plurality of ribs projecting from the top surface and the bottom surface of the body, each rib having a height above the body that decreases from the center of the body towards the periphery of the body, a sidewall protruding from the top surface and from the bottom surface at the periphery of the body and coupled to at least some of the plurality of ribs.

A portion of the body, a portion of the plurality of ribs, and a portion of the sidewall define a cavity allowing a volume of a gas to be trapped in the cavity when the disk is deployed on the surface of the body of liquid. The plurality of disks unite when floating on the surface of the body of liquid to form an arrangement of floating disks. Each of the plurality of disks includes an interlocking element configured to interact with a complementary interlocking element at an adjacent disk to assist in keeping the arrangement of floating disks together.

The foregoing embodiment may further include a plurality of apertures at the periphery of the body, the aperture allowing a liquid to pass through the top surface and the bottom surface. In some embodiments, the plurality of ribs are arranged in a pattern that is substantially identical at the top surface and at the bottom surface of the body. In other embodiments, the body includes a cross-sectional profile that that decreases from a center of the body towards the periphery of the body.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an arrangement of liquid covering disks.

FIG. 2 is a perspective view of a liquid covering disk.

FIG. 3 is an exploded perspective view of a portion of the liquid covering disk shown in FIG. 2.

FIG. 4 is a close up view of the texture of the material forming the liquid covering disk shown in FIG. 1.

FIG. 5 is a top plan view of the liquid covering disk of FIG. 2.

FIG. 6 is a cross-sectional view of the liquid covering disk of FIG. 2 along line 6-6 in FIG. 5.

FIG. 7 is a cross-sectional view of the liquid covering disk of FIG. 2 along line 7-7 in FIG. 5.

FIG. 8 is a side elevation view of the liquid covering disk of FIG. 2.

FIG. 9 is a cross-sectional perspective view of the arrangement of liquid covering disks of FIG. 1, illustrating interlocking features between disks.

FIG. 10 is an exploded cross-sectional view of interlocking features of liquid covering disks of FIG. 9.

FIG. 11 is top plan view of a second embodiment of a liquid covering disk.

FIG. 12 is a side view of the liquid covering disk of FIG. 11.

FIG. 13 is a top plan view of a third embodiment of a liquid covering disk.

FIG. 14 is a side view of the liquid covering disk of FIG. 13.

FIG. 15 is a top plan view of a fourth embodiment of a liquid covering disk, which includes spherical chambers.

FIG. 16 is a side view of the liquid covering disk of FIG. 15.

FIG. 17 is a top plan view of a fifth embodiment of a liquid covering disk.

FIG. 18 is a side view of the liquid covering disk of FIG. 17.

FIG. 19 cross-sectional view the embodiment of a liquid covering disk shown in FIG. 17 along line 19-19.

FIG. 20 is a perspective view of a sixth embodiment of a liquid covering disk, which includes cylindrical chambers.

DETAILED DESCRIPTION

The disclosed liquid covering disks and systems will become better understood through review of the following detailed description in conjunction with the figures. The detailed description and figures provide merely examples of the various inventions described herein. Those skilled in the art will understand that the disclosed examples may be varied, modified, and altered without departing from the scope of the inventions described herein. Many variations are contemplated for different applications and design considerations; however, for the sake of brevity, each and every contemplated variation is not individually described in the following detailed description.

Throughout the following detailed description, examples of various liquid covering disks are provided. Related features in the examples may be identical, similar, or dissimilar in different examples. For the sake of brevity, related features will not be redundantly explained in each example. Instead, the use of related feature names will cue the reader that the feature with a related feature name may be similar to the related feature in an example explained previously. Features specific to a given example will be described in that particular example. The reader should understand that a given feature need not be the same or similar to the specific portrayal of a related feature in any given figure or example.

The inventive subject matter provides systems and liquid covering disks that reduce evaporation, heat loss, reduce foam formation and emission of noxious or toxic fumes from an open liquid surface by forming a floating arrangement of liquid covering disks. The liquid covering disks include a body, a plurality of ribs projecting from the body, and a sidewall protruding at the periphery of the body. A portion of the body, a portion of the plurality of ribs, and a portion of the sidewall define a cavity.

A liquid covering disk including a number of such open cavities allows a volume of a gas to be trapped in the cavity when the disk is deployed on the surface of the body of liquid thereby providing buoyancy to the disk. Additionally, cavities with an open side facing the surface of the body of liquid provide the disks with a tendency to stick to the surface of the body of liquid. Furthermore, disks that are generally similar in shape tend to unite edge to edge when floating on the surface of the body of liquid to form an arrangement of floating disks that covers a major portion of an open liquid body. Complementary interlocking elements assist in keeping the arrangement of floating disks together.

The liquid covering disk has a polygonal shape in the horizontal floating plane, for example a triangular, quadrangular or hexagonal shape. The liquid covering disks may be hollow or solid. Some embodiments are made using a plastic having a gravity which is approximately one half the specific gravity of the liquid to provide the disk with the desired buoyancy.

With reference to FIGS. 1-10, a first example of a system for covering a surface of a body of liquid and liquid covering disk will now be described. Liquid covering disk 100 includes a body 120 having a top surface 112, a bottom surface 114, and apertures 132 at a periphery 122 of body 120. Apertures 132 are configured to allow a liquid and debris to pass through. Disk 100 further has a sidewall 116 protruding vertically at periphery 122 of body 120 and a plurality of ribs 124 projecting vertically from body 120.

A plurality of channels 126 are formed by portions of body 120, portions of ribs 124, and portions of sidewall 116. The channels are formed by ribs 124, protuberance 148, sidewall 116, and top surface 112. Each rib 24 has two surfaces which define faces of channels 126.

On each major side of disk 100, channels 126 slope downwards towards apertures 132 proximate sidewall 116. Channels 126 serve to direct water and other debris towards apertures 132 to allow the water and debris to exit channels 126 through apertures 132 on whatever side of disk 100 is oriented upwards. Of course, the channels on the side of disk 100 oriented downwards will be wholly or partially submerged in the liquid body.

As can be seen in FIGS. 2, 5 and 6, disk 100 includes a set of cavities 118 and cavities 144. Cavities 118 are disposed along the periphery of disk 100 whereas cavities 144 are located at the center of disk 100. Cavities 118 are defined by a portion 136 of body 120, portions 138 and 140 of ribs 124, and portion 141 of sidewall 116. Cavity 144 is defined by a substantially cylindrical protuberance 148 that projects from body 120 at the center of the hexagonal shaped body 120.

When floating on the surface of a body of liquid a volume of a gas, such as air, may be trapped in cavities 118 and 144 between the surface 128 of the body of liquid 130 and the surfaces of the cavities. The trapped volume of gas imparts increased stability and buoyancy to disk 100. Trapping air below the bottom surface of the disk in the cavities increases the buoyancy of the disk.

Cavities 118 and 144 increase the stability of liquid covering disk through pressure equilibrium principles. When a pocket of air is trapped in cavities 118 and 144 by the surface of a liquid, the pressure of that pocket of air will be in equilibrium with the local atmospheric pressure. Attempts to separate the disk from the surface of the liquid will have the effect of increasing the volume of the chamber of air sealed in the cavities. Increasing the volume of the sealed chamber will decrease the air pressure within the sealed chamber and create a pressure imbalance with the ambient air pressure. The net result is that disk 100 will resist separating from the surface of the liquid in response to wind or other forces because the ambient air will act on the liquid and the disk to maintain the pressure of air sealed in cavities 118 and 144 in equilibrium with the ambient air pressure.

When an arrangement of liquid covering disks is used, wind may push upon the rib faces and push the liquid covering disks more closely together and reduce gaps in the coverage between them. The liquid covering disks may unite as an arrangement 142 of floating disks disposed in edge to edge relationship with generally like disks to cover at least a major portion of a body of liquid. For example, a system 190 for covering a surface of a body of liquid including a plurality of disks 100 is shown in FIG. 1.

Liquid covering disk 100, or a collection thereof, function to reduce heat loss and evaporation, suppress waves, reduce foam formation, and prevent the emission of noxious or toxic fumes from a body of liquid on which liquid covering disk 100 is deployed. In operation, liquid covering disk 100 floats with top surface 112 approximately above surface 128 of a body of liquid 130 and bottom surface 114 approximately below surface 128 of body of liquid 130. Of course, the disk may flip over from time to time, reversing the orientation of the top and bottom surfaces.

Body 120 of disk 100 has a substantially hexagonal shape in a horizontal plane. Top surface 112 includes a substantially cylindrical protuberance 148 that projects from body 120 at the center of the hexagonal shaped body 120. Although protuberance 148 is substantially cylindrical in shape with a substantially flat top, this disclosure also contemplates protuberances that implement different designs as well.

A plurality of ribs 124 radiate from protuberance 148 extending from body 120. In particular, twelve trapezoidal ribs 124 on each side of disk 100 radiate out from protuberance 148 towards periphery 122 of body 120 where they merge with sidewall 116. As one can see in FIG. 2, the height of ribs 124 gradually descends as they approach sidewall 116 and merges with the sidewall at equal height. The outer edges of the ribs, i.e., the end of the ribs away from the top/bottom surface, defines the contours of the disk, for example contour 134 of disk 100.

Liquid covering disk 100 further includes a sidewall 116, formed by a projection of the hexagonal periphery of top surface 112 and bottom surface 114. In some embodiments, sidewall 116, top surface 112, and bottom surface 114 are coupled such that they form a unified body.

Sidewall 116 generally follows periphery 122 of hexagonal shaped body 120. However, at each side of the hexagonal shape, sidewall 116 includes a curvature, for example sigmoidal curvature 152. Curvature 152 includes a concave portion 154, where the sidewall deviates slightly inward, relative to the side of the hexagonal shape, towards the center of the body, and a convex portion 156, where the sidewall deviates slightly outward, relative to the side of the hexagonal shape, towards the center of the body.

Apertures 132 serve as a port that allows an amount of liquid to pass through freely. For example, apertures 132 are formed in body 120 proximate sidewall 116 and allow water and debris to flow through back into the main liquid body. Additionally, apertures 132 along the periphery reduce or prevent water from being trapped on the top surface of the disk.

Aperture 132 allows for a gap in body 120 and sidewall 116 so that when a collection of liquid covering disks are used in concert and are nested in a closed, packed pattern, liquid is allowed to easily pass through aperture 132, whereas other liquid covering disks in the tightly packed pattern may otherwise substantially restrict such flow. In some embodiments, disks may be provided with additional apertures or ports.

Bottom surface 114 is substantially similar to top surface 112, including a similar shape, size, and topography, except for a shift in the curvature along the sides of the hexagonal shape, i.e., concave portions at the top surface align with convex portions at the bottom surface, and vice versa.

For the sake of brevity, the elements of bottom surface 114 will not be described in detail. However, bottom surface 114, like top surface 112, includes a central protuberance and ribs that are substantially the same shape and size as the corresponding parts on top surface 112. Sidewall 116, however, along the sides of the polygonal shaped body includes a portion wherein the curvatures are the opposite of the curvatures at the top surface. In particular, at top surface 112 sidewall 116 includes sigmoidal curvature 152 whereas at bottom surface 114, sidewall 116 includes sigmoidal curvature 158, which is positioned as the inverse to sigmoidal curvature 152.

For example, FIG. 1 shows a split in sidewall 116 where a concave portion 160 curves inward below convex portion 156 of curvature 152 and a convex portion 162 curves outward below concave portion 154 of curvature 152. Although the patterns formed by the ribs 124 of top surface 112 and bottom surface 114 are substantially similar, this is not specifically required, and liquid covering disks with different top surfaces and bottom surfaces are equally within this disclosure.

Additional openings 164 and 166 are provided in the portions of body 120 where sidewall 116 curves outward, i.e., in top surface 112 and bottom surface 114 at the convex portions 156 and 162, respectively, of side wall 116. Openings 164 and 166 assist the disk in settling into a substantially flat position on the surface of the body of liquid and to communicate fluid between channels 126 and the body of liquid on which disk 100 floats. In some embodiments, the body, ribs, and sidewall may include additional openings.

Body 120 has a cross-sectional thickness that decrease from the center to edge 146 to facilitate dispersion of rain water and to avoid standing water. For example, the center of top surface 112 is at a higher elevation relative to its lateral periphery 122. However, in some embodiments liquid covering disks may include a substantially flat top surface and/or bottom surface. In other embodiments, either the top surface, bottom surface, or both, may include a depression, or lowers in elevation as one approaches the center, for example in combination with an opening.

The outer contours of the ribs follow a similar profile. Ribs 116 create channels which guide rain to the edges of the disks. Ribs 116 provide structural support to the disk and provide resistance to wind. The contour of the disk is determined by the height of the ribs and the sidewall.

The dimension of the cavities may depend on the application and wind resistance that is desired. The cavities can be sized to provide additional stability and buoyancy. In some embodiments, the size of the cavities is selected to allow the disks to float at a predetermined depth below the surface of the body of liquid.

In one example, a body has a diameter of about 8 inches and a height of at least about 0.5 inches. In another example, three liquid covering disks may cover about 1 square foot of surface of body of liquid. In some embodiments, the sidewall may have a height between 40% and 60% of the overall height of the disk.

FIG. 5 illustrates the position of the channels 126 created by the body, ribs, and sidewall. Disk 100 has a total of 48 channels, 24 channels at the top surface side of the body and 24 channels at the bottom surface side. Each side has a middle cavity at the center of the polygonal shape and 6 cavities at the peripheral edges.

Cavities 118 and 144 may capture a given amount of a gas when a liquid covering disk is placed in water or other liquid. The size and volume of the cavities may be selected to create desired buoyancy and surface adhesion characteristics. For example, the size and volume of the cavities may be selected to cause the buoyant force of the gas enclosed in cavities 118 and 144, combined with any buoyant force created by the density of the disk's construction material, to be sufficient to maintain the disk afloat on the body of liquid with its lower contours at a predetermined depth below the surface of the body of liquid.

In some embodiments, the disk may have cavities that are enclosed. In other embodiments, the disk may have cavities that are enclosed and filled with foam and other solids that are generally understood to include pockets of trapped gas. Further example embodiments may include cavities that are enclosed and partially filled with a fluid. In some examples, dense substances may be added to the body to provide more stability to the disk while positioned in a liquid body.

Liquid covering disks may hold differing quantities of gas into the cavities. By adjusting the shape of the body and the pattern of the ribs and sidewall, the size of the cavities is modified and the liquid covering disks may be designed to float at different depths, for example from about 10% to about 60% submerged when deployed on a body of liquid. These modifications may also be useful in adapting liquid covering disks for use in liquids of varying densities.

FIGS. 9 and 10 illustrate details of an interlocking mechanism 172 as used in an arrangement 142 of floating disks disposed in edge to edge relationship. Interlocking mechanism 172 includes portions of substantially identical disks 100 with curvatures on the sides of adjacent disks complementing and overlapping each other.

FIGS. 9 and 10 show disks 100, here referred to as a first disk 174 and a second disk 176, having interlocking elements 168 and 170, respectively. Interlocking element 168 is formed, for example, by the concave portions 54, 60 and convex portions 56, 62 of sidewall 116, as described above, on disk 168. Complementary interlocking element 170 is formed of similar concave portions 54, 60 and convex portions 56, 62 of a sidewall 116 of adjacent disk 176 which is oriented such that curvatures of each respective disk complements the other.

The interlocking elements are symmetrically positioned over the polygonal body and include protruding and recessing portions formed by alternating concave and convex portions. The concave and convex portions are designed to overlap with similar but inverse interlocking elements of adjacent disks.

Liquid disk covering 100 is shown in FIGS. 1-10 with a specific rib pattern and a hexagonal shape, but this shape is not explicitly required in every embodiment of liquid disk coverings. For example, the disk may take a wide variety of shapes, including, but not limited to, polygonal, elliptical, or non-polygonal shapes. Certain shape examples include interlocking elements, such as complimentarily configured projections and recesses positioned around the liquid covering disk's perimeter when viewed from above.

Turning attention to FIGS. 11-19, additional examples of a liquid covering disks are described. The liquid covering disks described hereafter includes many similar or identical features to liquid covering disk 100. Thus, for the sake of brevity, each feature of liquid covering disks 200, 300, 400, and 500 will not be redundantly explained. Rather, key distinctions between liquid covering disks 200, 300, 400, 500 and liquid covering disk 100 will be described in detail and the reader should reference the discussion above for features substantially similar between the liquid covering disks.

FIGS. 11 and 12 illustrate a second example of a liquid covering disk. Liquid covering disk 200 has a body 220, a sidewall 216, a plurality of channels 226, and plurality of ribs 224. Body 220 is substantially triangular shaped. Sidewall 216 projects around periphery 222 of body 220 similar to sidewall 116, described above, and including interlocking mechanism 272 having sigmoidal curvatures 252 and 258 along the sides of the substantially triangular shaped body 220. Ribs 224 radiate from a center cavity 244.

FIGS. 13 and 14 illustrate a third example of a liquid covering disk. Disk 300 has a body 320, a sidewall 316, a plurality of cavities 318, a plurality of channels 326, and plurality of ribs 324. Body 320 is substantially rectangular shaped. Sidewall 316 projects around periphery 322 of body 320, similar to sidewall 116 described above.

Disk 300 includes interlocking mechanism 372 having sigmoidal curvatures 352 and 358 along the sides of the substantially rectangular shaped body 320. Ribs 324 radiate from a center of disk 300. A central cavity may be formed at the center of the disk in addition or alternatively to the periphery cavities 318.

FIGS. 15 and 16 illustrate a fourth example of a liquid covering disk. Disk 400 has a body 420, a sidewall 416, a plurality of channels 426, and a plurality of ribs 424. Sidewall 416 projects around periphery 422 of body 420, similar to sidewall 116 described above, including interlocking mechanism 472 having sigmoidal curvatures 452 and 458 along the sides of the substantially hexagonal shaped body 420. Ribs 424 radiate from a center of disk 400. The pattern of the ribs 424 of disk 400 is similar to the pattern of ribs of disk 100 described above with reference to FIGS. 1-10.

A key difference between liquid covering disk 400 and liquid covering disk 100 lies in the placement of six spherical chambers 492, 493, 494, 495, 496, 497 at the vertices of the hexagonal shaped disk 400. Spherical chambers 492, 493, 494, 495, 496, 497 are positioned on, or form part of body 420, with symmetrical halves being part of top surface 412 and bottom surface 414. In some embodiments, spherical chambers may be filled with a gas or any suitable material that assists with buoyancy of disk 400. In further embodiments, spherical chamber may be filled with a dense material and contribute to the stability of the disk on the surface of the body of liquid.

FIGS. 17-19 show a fifth example of a liquid covering disk. Disk 500 has a body 520, a sidewall 516, a plurality of periphery vertices 518, a pair of central cavities 544, and a plurality of ribs 524. Ribs 524 radiate from central cavities 544. The pattern of ribs 524 is similar to the pattern of ribs of disk 100, described above with reference to FIGS. 1-10.

A key difference between liquid covering disk 500 and liquid covering disks described above is that vertices 518 are solid as opposed to hollow cavities or chambers. In the present example, vertices 518 are made from the same material as the other components of disk 500. However, the material forming vertices may be selected to impart desired buoyancy characteristics, such as a variety of structural foams.

The profile of disk 500 is conducive to stacking disks on top of each other during manufacturing and installation. Further, the profile of disk 500 is conducive to the disks sliding past each other when deploying the disks into a body of liquid.

Interlocking mechanism 572, having sigmoidal curvatures 552 and 558 along the sides of the substantially hexagonal shaped body 520, is substantially identical to interlocking mechanism 172 described above.

FIG. 20 shows a sixth example of a liquid covering disk, namely, liquid covering disk 600. Liquid covering disk 600 is substantially similar to liquid covering disks described above, including to liquid covering disk 400, and includes a plurality of channels 626. As the reader can see in FIG. 20, however, liquid covering disk 600 cylindrical chambers or cavities 696 instead of the spherical chambers included in liquid covering disk 400. Cylindrical chambers 696 may be open or unplugged, as shown in FIG. 20, or closed off or plugged to trap a volume of air within the cylindrical chamber. Plugging or unplugging the chambers will change the buoyancy of the liquid covering disk, with disks having plugged chambers being more buoyant.

The disks may be made of a material which resists chemicals, UV, and abrasion from friction between adjacent disks. FIG. 4 shows an example of a suitable material, an engineered micro-structure 180, which may be used for the body of the liquid covering disk.

In some embodiments, liquid covering disk 100 and all of its components are made of an ultraviolet stabilized material, such as ultraviolet stabilized high density polyethylene (HDPE). The use of ultraviolet stabilized high density polyethylene helps maintaining the disk's material integrity during outdoor use over an extended period of time. In liquid covering disk 100, for example, adding carbon black to the polyethylene, for example a ratio of about 2%, provides ultraviolet light protection and stabilization. In other embodiments, ultraviolet light protection or stabilization may be achieved by adding carbon black to the main constituent of the disk, such as high density polyethylene or polypropylene, for example in a ratio of about 2% to about 10%.

Examples of suitable constructions materials for disks include expanded polypropylene, high density polyethylene, and an expanded polypropylene using a blowing agent with UV stabilization. An expanded HDPE using a blowing agent with UV stabilization may also be used.

In some examples, an expanded polypropylene is used that was created using a process that expands plastics while in the solid state as opposed to conventional foaming techniques. Conventional foaming techniques can inadequately control bubble size in the plastic piece and require the use of potentially harmful foaming agents. One suitable solid state plastic expansion process is the Ad-air® process utilized by MicroGREEN Polymers, Inc.

Other suitable materials include an expanded polypropylene using a glass bubble or an expanded HDPE using a glass bubble.

In some embodiments, the disk may be formed in one piece but using a different materials and/or different color for the main body and ribs. Other embodiments may be formed as an assembly of parts, for example, a body provided with distinct ribs and a sidewall. Further example embodiments may be made by joining a top portion and a bottom portion to form disks as described above. In many examples, many features at the top surface and the bottom surface of the disks are identical, which simplifies manufacturing.

Some example embodiments of liquid covering disks may be made by injection molding techniques. For example, each half of a liquid covering disk may be made by an injection molding technique. The molded halves are then fused together using a hot plate, which allows for a “perfect weld” when working with high-density polyethylene. Other joining techniques can also be used, such as ultrasonic welding, high frequency welding, friction welding, spin welding, laser welding, hot gas welding, free-hand welding, and the like.

Other embodiments of liquid covering disks may be made by blow molding techniques. Blow molding may be desirable where high speed fabrication is required. Using blow molding techniques, disks can be made in one simple operation, removing the need for welding two halves.

Other example embodiments of liquid covering disks may be made by a combination of injection molding with air injection technologies which reduce the original polymer density and improve insulation properties.

Blow molding agents and glass spheres may be added to reduce density and improve physical properties. Some rib patterns may increase the disk's rigidity and thereby offset the increased elasticity and softness resulting from the use of the blowing agent. Because the ribs can be added separately from the body, a different material can be used where no blowing additive has been introduced. Adding the ribs separately can be done, for example, in one step by using a two material injection molding method where two types of thermoplastic resin are successively injected into the mold by respectively different injection cylinders, thereby producing a product with two types of resins and colors.

Liquid covering disks in this disclosure are often recited using terms such as “top” and “bottom” to better illustrate disks' relative vertical orientation. However, many liquid covering disks according to this disclosure, specifically including liquid covering disks 100, 200, 300, 400, and 500 may be turned over 180 degrees and be capable of substantially the same functionality. This may be particularly useful in windy conditions, in which a liquid covering disk may be flipped unintentionally.

The disclosure above encompasses multiple distinct inventions with independent utility. While each of these inventions has been disclosed in a particular form, the specific embodiments disclosed and illustrated above are not to be considered in a limiting sense as numerous variations are possible. The subject matter of the inventions includes all novel and non-obvious combinations and subcombinations of the various elements, features, functions and/or properties disclosed above and inherent to those skilled in the art pertaining to such inventions. Where the disclosure or subsequently filed claims recite “a” element, “a first” element, or any such equivalent term, the disclosure or claims should be understood to incorporate one or more such elements, neither requiring nor excluding two or more such elements.

Applicant(s) reserves the right to submit claims directed to combinations and subcombinations of the disclosed inventions that are believed to be novel and non-obvious. Inventions embodied in other combinations and subcombinations of features, functions, elements and/or properties may be claimed through amendment of those claims or presentation of new claims in the present application or in a related application. Such amended or new claims, whether they are directed to the same invention or a different invention and whether they are different, broader, narrower or equal in scope to the original claims, are to be considered within the subject matter of the inventions described herein. 

The invention claimed is:
 1. A disk configured to float on the surface of a body of liquid, comprising: a body including a top surface, a bottom surface, and an aperture at a periphery of the body, the aperture configured to allow a liquid to pass through the aperture; a plurality of ribs projecting from the body; a sidewall protruding at the periphery of the body; and a cavity defined by a portion of the body, a portion of the plurality of ribs, and a portion of the sidewall, the cavity allowing a volume of a gas to be trapped in the cavity when the disk is deployed on the surface of the body of liquid, wherein the volume of gas trapped in the cavity serves to fluid dynamically resist the disk separating from the surface of the body of liquid on which the disk floats.
 2. The disk of claim 1, wherein the body defines a polygonal shape.
 3. The disk of claim 2, wherein the plurality of ribs radiate outward from the center of the polygonal shape towards the edges of the polygonal shape.
 4. The disk of claim 1, wherein the plurality of ribs extend from the top surface and from the bottom surface of the body.
 5. The disk of claim 1, wherein the plurality of ribs have a height above the body that decreases from a center of the body towards the periphery of the body.
 6. The disk of claim 1, wherein the body includes a cross-sectional profile that decreases from a center of the body to the periphery of the body.
 7. The disk of claim 1, wherein the sidewall protrudes from the top surface and from the bottom surface.
 8. The disk of claim 1, wherein the sidewall includes a concave portion.
 9. The disk of claim 1, wherein the sidewall includes a convex portion.
 10. The disk of claim 1, wherein the aperture is positioned adjacent the sidewall.
 11. The disk of claim 1, wherein the sidewall includes a sigmoidal curvature along the periphery of the body.
 12. The disk of claim 11, wherein the aperture follows a contour of the curvature.
 13. A system for covering a surface of a body of liquid, comprising: a plurality of disks configured to float on the surface of the body of liquid, each disk comprising a body including a top surface, a bottom surface, and an aperture at a periphery of the body, the aperture allowing a liquid to pass through, a plurality of ribs projecting from the body, a sidewall protruding from the body at the periphery, and wherein a portion of the body, a portion of the plurality of ribs, and a portion of the sidewall define a cavity allowing a volume of a gas to be trapped in the cavity when the disk is deployed on the surface of the body of liquid; wherein the plurality of disks unite when floating on the surface of the body of liquid to form an arrangement of floating disks; and wherein each of the plurality of disks includes an interlocking element configured to interact with a complementary interlocking element at an adjacent disk to assist in keeping the arrangement of floating disks together.
 14. The system of claim 13, wherein the interlocking element includes a portion of the sidewall.
 15. The system of claim 13, wherein the interlocking element includes a curvature of the sidewall.
 16. The system of claim 13, wherein the interlocking element includes a sigmoidal curvature of the sidewall extending from the bottom surface of the body and an inverse curvature extending from the top surface at a corresponding location of the body.
 17. A system for covering a surface of a body of liquid, comprising: a plurality of disks configured to float on the surface of the body of liquid, each disk comprising a body having a substantial polygonal shape in the horizontal floating plane, the body including a top surface and a bottom surface, a plurality of ribs projecting from the top surface and the bottom surface of the body, each rib having a height above the body that decreases from the center of the body towards the periphery of the body, a sidewall protruding from the top surface and from the bottom surface at the periphery of the body and coupled to at least some of the plurality of ribs, wherein a portion of the body, a portion of the plurality of ribs, and a portion of the sidewall define a cavity allowing a volume of a gas to be trapped in the cavity when the disk is deployed on the surface of the body of liquid; wherein the plurality of disks unite when floating on the surface of the body of liquid to form an arrangement of floating disks; and wherein each of the plurality of disks includes an interlocking element configured to interact with a complementary interlocking element at an adjacent disk to assist in keeping the arrangement of floating disks together.
 18. The system of claim 17, further comprising a plurality of apertures at the periphery of the body, the aperture allowing a liquid to pass through the top surface and the bottom surface.
 19. The system of claim 17, wherein the plurality of ribs are arranged in a pattern that is substantially identical at the top surface and at the bottom surface of the body.
 20. The system of claim 17, wherein the body includes a cross-sectional profile that that decreases from a center of the body towards the periphery of the body. 